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Papir je zauzeo važno mjesto u povijesti čovječanstva, ali svojom raznolikošću i mogućnostima oblikovanja do danas ima važnu ulogu. Diplomski rad upoznaje o mogućnostima likovnog oblikovanja i tehnikama oblikovanja. Analizom povijesnog razvoja papira pratimo nastanak i razvojne faze proizvodnje papira, pregled različitih vrsta i namjena papira koje omogućuju zaista široku lepezu njegove primjene. Drugi dio rada bavi se mogućnostima likovnog oblikovanja papira te nastoji dati uvid u različite mogućnosti i tehnike oblikovanja. Papir kao zahvalan materijal za oblikovanje se vrlo često koristi u likovnom izražavanju u razrednoj nastavi, no iako ne spada u tradicionalne tehnike kiparskog oblikovanja umjetnici ga također rado koriste na najrazličitije načine; izražavaju svoje osjećaje, šalju poruke o današnjim problemima, o prolaznosti živog svijeta te o ostalim važnim stvarima koje nas okružuju i događajima svakodnevice. Throughout human history, paper has had a significant role, wich persists nowadays for its diversity an potetntial for distinct designs. This thesis presents the possibilities of visual arts design and techniques. Analaysing historical development of paper, we can trace its origin and manufacture formation stages as well asdistinct types and functions, which allow a wide array of application. The second part of the thesis deals with the possibilities of visual (fine) art paper design and aims to give an insight into various design options and techniques. Being such a grateful material, paper is very often use din fine arts in the classrom and even though it is not a traditional material for sculpting, artists sometimes gladly use it in various purposes: to express emotions; to send a message regarding current issues; to express the temporal nature of the living world and other relevant issues in the outside world.

The response of paper to humidity variations is a complex, inherently multi-scale problem. The hygroscopic swelling of individual fibres and their interactions within the fibrous network govern the macroscopic, sheet-level response. At this scale, moisture induced instabilities and out-of-plane deformations may occur, which are critical for a number of industrial applications. This work specifically focuses on several aspects of this important issue. A macroscopic phenomenological hygro-mechanical model is first proposed, which aims at predicting moisture induced out-of-plane deformations in paper sheets. The constitutive model is based on the relation between these deformations and typical irreversible phenomena associated to the history of paper manufacturing, i.e. the release of dried-in strains. The model is used to describe bending induced by moisture gradients through the thickness of the sheet as well as buckling due to moisture variation in the presence of mechanical constraints. The results of the model show that the anisotropic sheet-level hygro-expansion has a strong influence on the instability phenomena. Moreover, a comparison with experiments provides adequate semi-quantitative estimates. An additional step is made towards the multi-scale understanding of paper hygro-mechanics. The fundamental physical mechanisms governing the macroscopic moisture induced response are investigated on the basis of the underlying fibrous network. To this aim, a meso-structural model is developed which consists of a network of fibres randomly positioned in a planar region according to an orientation probability density function. A series of network simulations reveals that upon moisture content variations the expansion of the inter-fibre bonding regions essentially drives the overall deformation. Particularly in the case of anisotropic fibre orientation, this explains the origin of the macro-scale anisotropic hygro-expansion, which is essential for the observed sheet-level instability phenomena.

The cost of specialized scientific equipment can be high and with limited funding resources, researchers and students are often unable to access or purchase the ideal equipment for their projects. In the fields of materials science and mechanical engineering, fundamental equipment such as tensile testing devices can cost tens to hundreds of thousands of dollars. While a research lab often has access to a large-scale testing machine suitable for conventional samples, loading devices for meso- and micro-scale samples for in-situ testing with the myriad of microscopy tools are often hard to source and cost prohibitive. Open-source software has allowed for great strides in the reduction of costs associated with software development and open-source hardware and additive manufacturing have the potential to similarly reduce the costs of scientific equipment and increase the accessibility of scientific research. To investigate the feasibility of open-source hardware, a micro-tensile tester was designed with a freely accessible computer-aided design package and manufactured with a desktop 3D-printer and off-the-shelf components. To our knowledge this is one of the first demonstrations of a tensile tester with additively manufactured components for scientific research. The capabilities of the tensile tester were demonstrated by investigating the mechanical properties of Graphene Oxide (GO) paper and thin films. A 3D printed tensile tester was successfully used in conjunction with an atomic force microscope to provide one of the first quantitative measurements of GO thin film buckling under compression. The tensile tester was also used in conjunction with an atomic force microscope to observe the change in surface topology of a GO paper in response to increasing tensile strain. No significant change in surface topology was observed in contrast to prior hypotheses from the literature. Based on this result obtained with the new open source tensile stage we propose an alternative hypothesis we term 'superlamellae consolidation' to explain the initial deformation of GO paper. The additively manufactured tensile tester tested represents cost savings of >99% compared to commercial solutions in its class and offers simple customization. However, continued development is needed for the tensile tester presented here to approach the technical specifications achievable with commercial solutions.

The present work describes the construction of a semi-analytical model for prediction of buckling loads in simply supported corrugated paperboard panels. The model accounts for transverse shear, due to the weakness of the core in such plates compared to the facings. This was done utilizing energy relations and rst order transverse shear. The panel was homogenised using laminate theory. A detailed model using FEM was derived in order to validate the predictive capabilities of the analytical model. Experimental testing was performed to estimate the accuracy of both theoretical models, and assess the limitation of the analytical model. All modes of analysis showed good agreement for cubic boxes. Further investigation into expanding the scope of the analytical model was carried out and commented on.